[media] media: s5p-mfc: fix compilation issue on archs other than ARM (32bit)

This patch fixes build break caused by lack of dma-iommu API on ARM64
(this API is specific to ARM 32bit architecture).
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>

drivers/media/platform/s5p-mfc/s5p_mfc_iommu.h

@@ -14,7 +14,7 @@
 #define S5P_MFC_IOMMU_DMA_BASE	0x20000000lu
 #define S5P_MFC_IOMMU_DMA_SIZE	SZ_256M
 
-#ifdef CONFIG_EXYNOS_IOMMU
+#if defined(CONFIG_EXYNOS_IOMMU) && defined(CONFIG_ARM_DMA_USE_IOMMU)
 
 #include <asm/dma-iommu.h>